Two cases of schizencephaly associated with cytomegalovirus (CMV) infection are reported from the University La Sapienza, Rome, and Dibit Scientific Institute, Milan, Italy. In patient 1, MRI showed a left schizencephaly with a polymicrogyric cortex lining the clefts; CMV DNA was demonstrated in the serum on the second day of life. Patient 2 was referred at 4 years of age, and MRI showed a large, open left schizencephaly, surrounded by polymicrogyric cortex, and cerebellar hypoplasia. CMV DNA was detected in the serum, the early history revealed intrauterine growth retardation, microcephaly, petechiae, cataract, hepatospenomegaly,anemia, and periventricular calcifications were present on CT at 3 months of age. Tests for a genetic origin of the schizencephaly failed to demonstrate the characteristic mutation in the homeobox gene EMX2. 
COMMENT. Prenatal cytomegalovirus infection may be a factor in the pathogenesis of some cases of schizencephaly and other neuronal migration disorders. Yakovlev and Wadsworth who coined the term schizencephaly (1946) timed the formation of the clefts in the 2nd month of fetal development.